Unverricht-Lundborg disease is a rare inherited form of epilepsy. Affected individuals usually begin showing signs and symptoms of the disorder between the. Unverricht-Lundborg disease (EPM1; OMIM ) is the most common of the rare genetically heterogeneous progressive myoclonic. Unverricht-Lundborg disease (ULD), progressive myoclonic epilepsy type 1 ( EPM1, OMIM), is an autosomal recessively inherited.
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Unverricht—Lundborg disease abbreviated ULD or EPM1 is the most common form of an uncommon group of genetic epilepsy disorders called the progressive myoclonus epilepsies.
Onset of the disease is characterized by myoclonic jerks and tonic-clonic seizures. Patients with Unverricht—Lundborg disease exhibit myoclonic jerks and tonic-clonic seizures at a young age, between ages 6— The myoclonic jerks occur in the muscles of the arms and legs closest to the torso, and are triggered due to a variety of common external stimuli. The genetic cause of ULD is known, but research has led to new areas of study that may lead to an increase in knowledge of what causes ULD.
The cause of ULD is known to be a mutation of the gene that produces cystatin B. New research shows that cystatin B may not be the only factor involved in Unverricht—Lundborg disease. In a study, it was determined that patients with ULD had more dopamine receptors in certain areas of their brain than unaffected individuals.
The results of this study indicate that the cause of ULD may be more complex than currently thought. While the genetic cause of Unverricht—Lundborg disease is known, the mechanism by which it works is not fully known.
Orphanet: Enfermedad de Unverricht Lundborg
Current research has provided promising results that may lead to a confirmation of the mechanism. This research has been performed on mice with the gene for producing cystatin B removed, to provide a similar set of symptoms to individuals with ULD. It has shown that a lack of cystatin B due lkndborg a mutation of the CSTB gene leads to a decrease in the number of inhibitory neurons, and this lack of inhibition makes the cells in the brain, particularly the hippocampusmore excitable.
It is hypothesized that this increase in excitability is what causes the myoclonic jerks and tonic-clonic seizures in patients with ULD. Research also gives evidence to support the idea that cystatin B may be a type of “protecting” molecule in the brain. Normally, after a seizure, the presence of cystatin B prevents the neurons from dying due to toxic levels of neurotransmitters.
Studies suggest that the absence of cystatin B leads to the death of affected neurons, leading to a damaged portion of the brain. This damage coupled with the increased excitability of the cells then leads to more damage, which is what makes Unverricht—Lundborg disease progressive.
The only currently available method to diagnose Unverricht—Lundborg disease is a genetic test to check for the presence of the mutated cystatin B gene. If this gene is present in an individual suspected of having the disease, it can be confirmed. However, genetic tests of this type are prohibitively expensive to perform, especially due to the rarity of ULD. In most cases, a misdiagnosis is not detrimental to the patient, because many of the same medications are used to treat both ULD and whatever type of epilepsy the patient has been misdiagnosed with.
However, there are a few epilepsy medications that increase the incidence of seizures and myoclonic jerks in patients with ULD, which can lead to snfermedad increase in the speed of progression, including phenytoin enfetmedad, fosphenytoinsodium channel blockersGABAergic drugsgabapentin and pregabalin.
Other methods to diagnose Unverricht—Lundborg disease are currently being explored. While electroencephalogram EEG is useful in identifying or diagnosing other forms of epilepsy, the location of seizures in ULD is currently known to be generalized across the entire brain.
Without a specific region to pinpoint, it is difficult to accurately distinguish an EEG reading from an individual with ULD from an individual with another type of epilepsy characterized by generalized brain seizures.
However, with recent research linking ULD brain damage to the lundbkrg,  the usefulness of EEG as a diagnostic tool may increase. While MRIs taken during the onset of the disease are generally similar to those of individuals without ULD, MRIs taken once the disease has progressed show characteristic damage,  which may help to correct a misdiagnosis. While ULD is a rare disease, the lack of well defined cases to study and the difficulty in confirming diagnosis provide strong evidence that this disease is likely under diagnosed.
Progressive myoclonic epilepsies generally constitute only a small percentage of epilepsy cases seen, and ULD is the most common form. While ULD can lnudborg to an early death, it is considered to be the least severe form of progressive myoclonic epilepsy. While there is no current cure to repair the mutated CSTB gene, several antiepileptic drugs are effective in reducing seizures and helping patients with ULD to manage the symptoms.
In addition, new research is being performed to examine the effectiveness of other types of treatments. Valproic enferjedad is the first line drug entermedad for reducing generalised seizures and myoclonus.
Levetiracetam is also effective for both generalised seizures and myoclonus. Clonazepam and high-dose piracetam can alleviate myoclonus. Phenytoin can worsen seizures and may speed up neurodegeneration ; carbamazepineoxcarbazepinetiagabinevigabatringabapentin and pregabalin may worsen myoclonus and myoclonic seizures.
If an individual with Unverricht—Lundborg disease is particularly sensitive to a enrermedad type of stimulus, it is also beneficial to reduce the patient’s exposure to that stimulus in order to reduce the likelihood of seizures.
For early Unverricht—Lundborg disease patients, the disease would begin to progress early and lack of effective treatment meant a quick progression. In many cases the patient would require a wheelchair for mobility, and unverriht die at a young age.
However, increased knowledge about the disease and improved treatment and medication has led to a dramatic improvement in prognosis for individuals with ULD. Antiepileptic drugs reduce the occurrence of seizures and myoclonus, which leads to a decrease in the damage caused in the brain due to seizures and the body due to falls resulting from the seizures.
As a result, individuals with Unverricht—Lundborg disease are now much less likely to end up in a wheelchair, which eliminates the chance of complications involved with being a wheelchair user.
Due to the progressive nature of the disease, depression is prevalent,  but support of family and friends as well as proper treatment can help.
While early patients with ULD had a life expectancy of around 24 years,  there have recently been reported cases of individuals living to near-normal ages. The only country that Unverricht—Lundborg disease has a reported incidence is in Finland, where it is reported to occur in 4 inindividuals.
Other countries with known cases include countries in the Mediterranean region including Italy, France, Tunisia, Algeria, and Morocco,  as well as the United States. Unverricht—Lundborg disease was first known as one of two different diseases, depending on the location of the individual who had it: Baltic unvverricht or Mediterranean myoclonus. Eventually, both were realized to be the same disease, ULD. Many studies have been performed recently to investigate the cause, mechanism, and chemical basis of Unverricht—Lundborg disease.
A recent study has attempted to describe the behavior of normal and mutated cystatin B as it is expressed in the body.
The results show that cystatin B has a polymeric structure, and that the mutated form of cystatin B, which is present in patients with Unverricht—Lundborg disease, is likely to attract other molecules of cystatin B and form clumps of the molecule. The researchers suggest that this clotting action of the cystatin B molecules may be one of the factors that cause progression of ULD.
In humans it is generally known that unless a patient has both recessive CSTB genes are homozygous recessivethey will not express ULD symptoms. A recent study has attempted to characterize the effects, if any, seen in mice that carry only one unvverricht CSTB gene are heterozygous.
The researchers analyzed normal and heterozygous mice by having them perform various tasks. The study found that heterozygous mice performed similar to normal mice when the task was unvrericht, but as the task continued or became more complex they were more likely to fail.
While the results for the heterozygous mice were not remarkably different from the normal mice, they do indicate that carrying just one recessive CSTB gene may have adverse effects, at least in enfermedaf. Currently, electroencephalography EEG is not very effective as a diagnostic tool for Unverricht—Lundborg disease. The results show that certain brain waves that are present at the lundboorg of ULD progression and are also present in unaffected individuals, including spontaneous generalized spike or polyspike wave discharges and lundbkrg response, tend to decrease after 10 to 15 years.
From Wikipedia, the free encyclopedia. Dtsch Z Nervenheilk ; 7: Leipzig und Wien, F. Ueber Degeneration und degenerierte Geschlechter unverrichg Schweden.
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Unverricht–Lundborg disease – Wikipedia
Sudden unexpected death in epilepsy Todd’s paresis Landau-Kleffner syndrome Epilepsy in animals. Retrieved from ” https: Autosomal recessive disorders Ejfermedad types Rare diseases. Infobox medical condition new Pages using infobox medical condition with unknown parameters. Views Read Edit View history.